The analysis of macromolecular structures by X-ray crystallography provides data critical for an understanding of the beneficial and adverse functions of biological macromolecules and assemblies associated with cancer, which is the focus of research in the Cancer Center's Structural Biology Program. Current studies embrace a wide range of crystallographic research pertaining to basic processes associated with cancer as well as to its prevention and treatment. As a new initiative of the Purdue Cancer Center, the establishment of a Macromolecular Crystallography Shared Resource Core Facility will promote a strong program of cancer-related crystallographic research as well as stimulate new research and additional cross-program collaborations. The essential service of the Resource will be to provide advanced facilities for macromolecular crystallography and experienced technical support to maintain these facilities in superb working condition for direct use by Cancer Center researchers. The proposed shared resource incorporates the extensive existing shared assets of the Structural Biology Program Area and provides access to all Cancer Center members. The essential facilities include laboratories equipped for X-ray diffraction experiments and for the crystallization of macromolecules. Key diffraction instruments include two I2kW rotating anode X-ray generators and three imaging plate diffractometers equipped with focusing mirror optics and cryogenic crystal cooling devices. Equally critical to the success of the shared resource is the involvement of very experienced support personnel. The X-Ray diffraction equipment which will be incorporated into this resource is currently heavily and exclusively used by Cancer Center members.